Dark Blue vs Imperial Blue

How close are they?

ΔE 19.5, loose: different enough that you should pick on purpose. Imperial Blue is noticeably lighter, more muted, cooler than Dark Blue.

✓ Herrick Games paint comparison chart lists these two as equivalents.

Can I use Imperial Blue instead of Dark Blue?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Imperial Blue is noticeably lighter, more muted, cooler than Dark Blue.

Can I use Dark Blue instead of Imperial Blue?

The same difference applies the other way round: Dark Blue is noticeably darker, more saturated, warmer.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.